The present invention pertains generally to frame structures and, more particularly, to elevated frame structures with interconnected linear members, and which can be assembled by a home owner or end user without the use of fasteners.
Bed frames are used to support a box spring and mattress several inches off the floor, and are commonly mounted upon casters at the four corners and intermediate points of the frame. Typically the bed frame consists of a plurality of generally L-shaped side and cross frame members detachably secured to one another for supporting the mattress and box spring unit between a foot board and head board. In the industry, the frame members are made from recycled railroad rail steel which is heated, re-shaped and processed into the L-shaped configuration. This recycled steel has very high carbon content and high strength as compared to conventional structural component materials. In the prior art, the generally orthogonal frame members are connected at the intersections by brackets which are attached to the ends of the frame members. For example, U.S. Pat. No. 3,683,429 describes a bed frame wherein several bracket pieces are attached to both of the intersecting frame members. Frames are supported by casters held by caster mounting brackets which are attached to the frame members. The casters are held by brackets which are attached to the frame members. The steel from which such brackets are made is of significantly lower strength than that of the frame members. Thus, the strength of the frame members is not utilized at the intersections, where high load and moment forces occur. Also, the brackets represent a number of parts which must be fabricated and separately attached to the frame members. Some frame designs which include a center rail within a rectangular frame require as many as 22 or more bracket pieces and 44 to 48 or more fasteners such as rivets.
In some prior art bed frames, the box spring supporting surfaces of the intersecting frame members are not flush, i.e., not in the same plane. This occurs as a result of the complex bracket assemblies used to form the intersections, particularly those which rely on a tapered wedge type connection. Consequently, the wooden frame of a box spring and the mattress will warp and sag when placed on such frames, especially in the center. A bed frame which utilizes the substantial strength of the frame members as an integral component of the frame intersections, which eliminates many bracket pieces, and which provides a truly flush support surface is not provided by the prior art.
The present invention overcomes these and other disadvantages of the prior art. The bed frame structures utilize the terminal ends of the rail members as integral structural connections to universal unibody caster mounts at the intersections of the rail members. Slots in the caster mounts are configured to accept a portion of a rail member to precisely align the horizontal flanges of the intersecting rails to provide a truly flush support surface for a mattress box spring. No bracketry is required at the ends of the rail members for connection to the caster mounts. The caster mounts are of a universal configuration at each rail intersection. The rail-accepting slots in the caster mounts are configured to accept and frictionally bind one or two rail flanges. The caster mount rail-accepting slots can be formed by displacement of material from an adjacent wall of the caster mount, thus creating a double wall thickness which supports an interlocking notch in the rail.
In accordance with one general aspect of the invention, there is provided a bed frame structure which includes rail members interconnected to form a generally orthogonal frame structure, each rail member having at least one flange oriented in a horizontal plane, the rail members including laterally opposed and spaced apart side rails, and opposed spaced apart transverse rails which extend generally perpendicularly between the side rails, with ends of the transverse rails positioned proximate to the side rails, a caster mount located at each end of the transverse rails, each caster mount having a main body, a top wall, a side wall, and a caster shank receiving ferrule, the top wall of each caster mount fastened to a side rail proximate to the ends of the transverse rails, and a rail receiving slot in the caster mount, wherein the rail receiving slot in the caster mount is in the top wall of the caster mount, and extends generally to a point of intersection of the top wall and the side wall and ends of the transverse rails having a notch and an end section proximate to the notch, the end section adapted to fit in the slot in the caster mount, and the notch adapted to fit over the side wall of the caster mount.
In accordance with another general aspect of the invention, there is provided a bed frame caster mount for connection of at least two rails of a bed frame and a caster, the caster mount having a body with a generally horizontal top wall dimensioned for attachment to a first rail of a bed frame, a side wall connected to and extending generally downward from the top wall, and a caster shank receiving ferrule connected to or extending from the side wall, a slot formed in the top wall and adapted to receive a portion of a second rail of a bed frame, the portion of the second rail received in the slot extending through the top wall and located proximate to the side wall, and another portion of the second rail positioned on top of the top wall and substantially flush with the portion of the first rail on the top wall of the caster mount.
These and other aspects of the invention are herein described in detail with reference to the accompanying Figures.